In the U.S., most crimes of violence are covered by state law, not federal law. Thirty-eight (38) states currently recognize the "unborn child" (the term usually used) or fetus as a homicide victim, and twenty-three (23) of those states apply this principle throughout the period of pre-natal development.[2] These laws do not apply to legally induced abortions. Federal and state courts have consistently held that these laws do not contradict the U.S. Supreme Court's rulings on abortion.

In 2004, Congress enacted, and President Bush signed, the Unborn Victims of Violence Act, which recognizes the "child in utero" as a legal victim if he or she is injured or killed during the commission of any of the 68 existing federal crimes of violence. These crimes include some acts that are federal crimes no matter where they occur (e.g., certain acts of terrorism), crimes in federal jurisdictions, crimes within the military system, crimes involving certain federal officials, and other special cases. The law defines "child in utero" as "a member of the species Homo sapiens, at any stage of development, who is carried in the womb."

Of the 38[2][3] states that recognize fetal homicide, approximately two-thirds apply the principle throughout the period of pre-natal development, while one-third establish protection at some later stage, which varies from state to state. For example, California treats the killing of a fetus as homicide, but does not treat the killing of an embryo (prior to approximately eight weeks) as homicide, by construction of the California Supreme Court.[4] Some other states do not consider the killing of a fetus to be homicide until the fetus has reached quickening or viability.[5]

Fetal homicide laws, as well as ordinary murder statutes, are increasingly used to prosecute pregnant women accused of intentionally or recklessly causing miscarriages or stillbirths. According to the organization National Advocates for Pregnant Women, South Carolina, one of the first states to pass a foeticide law, has charged only one man who assaulted a pregnant woman under this law, while approximately 300 women have been arrested. Widely publicized cases include that of Rennie Gibbs, Bei Bei Shuai, and Purvi Patel.

Gibbs was charged with murder in Mississippi in 2006 for having a stillborn daughter while addicted to cocaine. Gibbs is the first woman in Mississippi to be charged with murder relating to the loss of her unborn baby.[3] The judge in that case ruled that the charges be dismissed.[7] In 2011 Shuai was charged by Indiana authorities with murder and foeticide after her suicide attempt resulted in the death of the child she was pregnant with. Shuai's case was the first in the history of Indiana in which a woman was prosecuted for murder for a suicide attempt while pregnant.[8] In 2013 Shuai pleaded guilty to a misdemeanor charge of criminal recklessness and was released, having been sentenced to time served. In 2015 Purvi Patel became the first woman in the United States to be charged, convicted, and sentenced on a foeticide charge.[9] However, her conviction was later overturned, and she was resentenced to time served for a lesser charge.[10]

A sign in an Indian hospital stating that prenatal sex determination is a crime. The concern is that it will lead to female foeticide.

In medical use, the word "foeticide" is used simply to mean causing the death of the fetus, usually prior to some form of abortion. The Royal College of Obstetricians and Gynaecologists recommends foeticide be performed "before medical abortion after 21 weeks and 6 days of gestation to ensure that there is no risk of a live birth".[14] In abortions after 20 weeks, an injection of digoxin or potassium chloride into the fetal heart to stop the fetal heart can be used to achieve foeticide.[15][16][17][18][19] In the United States, the Supreme Court has ruled that a legal ban on intact dilation and extraction procedures does not apply if foeticide is completed before surgery starts.[19]

Injecting potassium chloride into the heart of a fetus causes immediate asystole, but depending on the method used, digoxin may fail to induce fetal demise in some cases (up to 5% if injected into the fetus and up to a third if injected into the amniotic sac)[20] even though it is the preferred drug in many clinics. Digoxin is preferred because it is technically difficult to inject KCl into the heart or umbilical cord.[21]

The most common method of selective reduction—a procedure to reduce the number of fetuses in a multifetus pregnancy—is foeticide via a chemical injection into the selected fetus or fetuses. The reduction procedure is usually performed during the first trimester of pregnancy.[22] It often follows detection of a congenital defect in the selected fetus or fetuses, but can also reduce the risks of carrying more than three fetuses to term.[23]